If you're going to add wood-dust
: to your filler you'll find it will come out much darker than the
: surrounding wood. Don't know what others do but I did my filling with
: epoxy and I mixed up different colours by blending wood-dust and West
: System microlite (light tan colour) and sometimes a bit of glue powder
: (white) to get whatever colour I was after.

I worked in a commercial cabinet shop for years, and when we did bent laminations, usually in a vacuum bag, we always added about 10% corn starch to standard white glue to make it stiffer and prevent spring-back. It's white and would also be a good product to add to lighten fairing/filling putty.

You might want to wipe the
: area around where you've filled with a rag moistened with acetone to
: remove the filler from the fibres of the surrounding wood. I nearly had a
: pretty bad visual disaster with this...........

Part of the problem when filling is that the filler fills the grain of the surrounding wood, not just the crack you're trying to fill. When I have to fill cracks in furniture I always put masking tape on either side of the crack so that none of the filler gets into the pores of the adjacent wood. Same is good on a kayak. I've never tried it with staples, but when shooting pin nails or brads, if I'm going to fill the hole with putty afterwards, I put down masking tape first, then shoot through the tape. That way the hole in the tape is exactly the size and shape of the hole in the wood that needs to be filled, and there is no risk of getting it in the pores of the wood surrounding the hole.

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